数字图像处理：（1）输入图像，采用半色调技术并将图像打印和显示。（2）按要求降低图像的灰度级。（3）采用像素复制的方法对图像进行缩放。（4）采用双线性插值法的方法对图像进行缩放。-Image Printing Program Based on Halftoning The following figure shows ten shades of gray approximated by dot patterns. Each gray level is represented by a 3